Written between two world wars, Samuel Barber's "Adagio for Strings" is a lament that is both "reflective and forward-looking," said Vladimir Kulenovic, music director for the Lake Forest Symphony. Called the saddest music ever written, the Adagio will serve as the opening piece for Lake Forest Symphony's first concert program of the season Sept. 10 and 11.

The concert is a tribute to the heroes and victims of the Sept. 11, 2011 terrorist attacks as well as all war veterans.

"Our opening concerts fall exactly 15 years after the tragedy of 9/11," Vladimir said. "As artist and human beings, we felt that we all have an emotional need and ethical responsibility to reflect upon it in the most meaningful way that we can as musicians."

The concert begins with Barber, continues with a Beethoven concerto performed by guest violinist Stefan Milenkovich, and concludes with Beethoven's Eroica Symphony, which exudes a type of "courageous optimism," Kulenovic said.

Susan Lape, the symphony's executive director, said the selections offer a "balance between somber recognition and hopeful heroism. These two pieces are juxtaposed at the beginning and the end for that reason," she said of the Barber and Beethoven.

"To commemorate life events, we have music," Lape said. "Music can help with the processing and the healing."

Before the first piece, the concert will begin with the National Anthem and a color guard, something typically not done at the symphony's concerts, Lape said.

Then the audience will hear the slowly moving notes of violins that swell and contract moving from minor to major to minor chords, in Barber's "Adagio."

"It's powerful, moving," said Lape. "It's quite intense. We thought that it captured the emotions of what people reflect about 9/11."

Kulenovic chose Stefan Milenkovich to perform Beethoven's Violin Concerto in D Major because he "is truly a phenomenally great violinst."

Kulenovic said he and Milenkovich are both from Belgrade in Serbia. "He also opened our season two years ago, and we were all waiting for the first available opportunity to have him back," Kulenovic said.

Awarded Serbia's Artist of the Century, Milenkovich has also performed with the Berlin Symphony Orchestra, Indianapolis Symphony Orchestra and many others worldwide.

The Beethoven violin concerto leads the way to the symphony's finale, Beethoven's Third Symphony, called the Eroica, which was written about Napoleon, who Beethoven thought was heroic, Lape said. "It has this big heroic theme that's wonderful and memorable," she said.

Kulenovic said her hears within the symphony "a tireless purist of justice," which can "inspire us in difficult times and celebrate our perseverance."